1. Field of the Invention
The invention pertains to the field of beverage formulations. More particularly, the invention pertains to formulations of powdered beverage mix containing rapidly dissolving calcium.
2. Description of Related Art
Calcium is the most abundant mineral in the body and is a major constituent of bone and teeth. Calcium is also involved in several physiological systems such as blood clotting, increasing cell membrane permeability, activating a number of enzymes, and acting as component in neural transmission and muscular contraction. Calcium deficiency may be a factor in the development of osteoporosis in elderly people.
Since the body does not produce calcium, it is totally dependent on external supply of calcium, which is nutritional or supplementary. Calcium may be obtained from various dietary sources, of which the primary sources are dairy products, in particular milk. Milk, however, is not generally consumed in sufficient quantities by the general population to obtain needed levels of calcium. One reason is that milk may be unattractive as a drink for social occasions. Also, a significant number of individuals are lactose intolerant, resulting in gastrointestinal problems if milk is consumed.
To increase the consumption of calcium, a more appealing alternative to milk is apparently needed. Beverages, which are consumed often by the general public, have been used as a vehicle for achieving greater calcium intake. Calcium supplementation in beverages, however, has been generally limited to liquid beverages. For example, Sunny Delight(copyright) Orange with Calcium of Procter and Gamble, Cincinnati, Ohio, USA, contains calcium citrate malate and is labeled as being protected by U.S. Pat. No. 4,737,375. Tropicana(copyright) Orange with Calcium of Tropicana Products, Inc., Bradenton, USA, also contains calcium citrate malate and is labeled as being protected by U.S. Pat. No. 4,722,847. Minute Maid(copyright) Orange with Calcium of the Coca-Cola Company, Houston, Tex., USA, contains calcium lactate and tricalcium phosphate according to U.S. Pat. No. 4,871,554.
Powdered beverage mix, which is reconstituted with water before drinking, is a potentially good vehicle for calcium delivery given the popularity of such brands as Kool-Aid(copyright) and Country Time(copyright) of Kraft Foods Inc., White Plains, N.Y., USA. Powdered beverage mix has a longer shelf life and is more portable than liquid beverages.
A significant problem with calcium supplementation of powdered beverage mix is that the calcium source must rapidly dissolve, within less than about 60 seconds of stirring by hand. When highly soluble salts of calcium are used, undesirable taste becomes a problem. For example, calcium acetate tastes vinegary, calcium chloride salty. When insoluble salts are used, grittiness can be a problem; moreover, the calcium source sediments rapidly out of solution which makes the reconstituted product aesthetically unpleasant, and which may lead to incomplete intake of the added calcium.
It has been found that organic salts of calcium are generally more bioavailable than the inorganic salts. For example, U.S. Pat. Nos. 4,772,467 and 5,128,374 teach the use of calcium citrate and calcium citrate malate, respectively, to treat osteoporosis. Calcium citrate and calcium malate are fairly insoluble and their direct use in powdered beverage mix can lead to problems previously described with insoluble calcium salts. However, calcium citrate can be formed in-situ by reacting a fairly insoluble calcium base selected from calcium carbonate, calcium oxide, and calcium hydroxide with citric acid as described in U.S. Pat. No. 4,851,221. The calcium citrate thus formed is in a metastable state, which eventually precipitates to the low equilibrium solubility of calcium citrate. Long-term stability of the metastable calcium citrate is not important in a powdered beverage mix as the reconstituted beverage is used immediately.
U.S. Pat. No. 4,851,221, however, does not teach the formulation of a powdered beverage mix containing calcium hydroxide and citric acid where on constitution with water, the acid-base reaction occurs very rapidly resulting in no visible or very minimal calcium sedimentation when stirred by hand for less than about 60 seconds.
The present invention provides a powdered beverage mix comprising i) flavor(s), ii) calcium hydroxide, iii) citric and/or malic acid and, iv) a sugar selected from sucrose, fructose, glucose, and combinations thereof, wherein the ratios of acid/sugar and sugar/calcium are selected such that the calcium in the powdered beverage mix dissolves rapidly with very minimal calcium sedimentation when stirred by hand for less than about 60 seconds.